Such a sorting machine for sorting flat objects, in particular postal items or "letters", comprises:
a sorting carousel having a plurality of pockets moving along guide rails, PA1 one or more input feeders to which the objects are fed one by one, manually or automatically, after determining the post (ZIP) code, to be fed into the pockets by means of a feed device, and PA1 a plurality of outputs where the letters for the same destination are discharged and stacked in the same tray or an equivalent.
Such a sorting machine is described in French patent FR 2 454 338, where the feed of the objects is effected by horizontal conveyor belts alternating with wheels which can be raised by an actuator to direct the objects in the travel direction of the pocket path to insert the objects into a channel which can be pivoted by a motor between a substantially horizontal position in which it can receive the object to be fed, and a substantially vertical position in which it can discharge the object into the corresponding pocket. The channel includes an output chute closed by a pivoting gate controlled by a lever operated by an operating device.
The invention provides a feed device with higher performance, which allows a particularly high rate of operation, while being simple, compact and adapted to a large range of mail.
The feed device is intended in particular for fitting in a sorting machine including a carousel, fed by a plurality of input feeders, serving up to 180 sort destinations and capable of a minimum flow rate of six objects per second. In order to limit the speed of the carousel, the objects are transported in pockets along a direction normal to their surface. Since the pitch between carousel pockets is around 90 mm, this flow of objects is obtained with a minimum transfer speed of 0.54 m/s.
The maximum number of input feeders is such that it remains compatible with the minimum flow of six objects per second. Taking into account the flows which can be attained by the three types of input feeder that are envisaged (with manual presentation and coding, around 0.7 objects/second; with automatic presentation and manual coding, around 1.1 objects/second; with manual presentation and optical reading, around 1.8 objects/second), feeders can be provided in number and of types such that their total flow rate does not exceed the flow rate of the conveyor.
The said sorting machine allows a particularly large range of mail to be processed. By way of example, the area L by h can vary from 145 mm by 250 mm to 225 mm by 353 mm, the thickness being from 0.5 mm to 20 mm and the weight from 10 g to 500 g. Moreover the feed device should suit any kind of mail, regardless of its rigidity or flexibility, whatever its wrapping (rigid card or flexible plastic).